Powell, 52, completed his third season as Houston's assistant hitting coach. This year, the Astros led the Major Leagues in many significant offensive categories, including runs (896), batting average (.282), on-base percentage (.346) and slugging percentage (.478). They also ranked second in the Majors with 238 home runs.
By comparison, the Giants ranked last in the Majors in homers (128) and slugging (.380). They finished next-to-last in runs (639) and on-base percentage (.309) and were 23rd in batting average (.249).
That spelled the end of Hensley Meulens' eight-year stint as San Francisco's hitting coach, though he will remain on manager's Bruce Bochy's staff as bench coach.
Powell, who has coached and managed in professional baseball since 2002, is a graduate of San Francisco's Lincoln High School. Primarily an outfielder, he signed with the Giants as an undrafted free agent in 1983 before being traded to Montreal with left-hander George Riley for right-hander Bill Laskey on Oct. 24, 1985.
Powell had stints in the Majors with Montreal in 1987 and Seattle in '91. He hit .211 with three homers and 16 RBIs in 71 games with those clubs.
A right-handed batter, Powell had a productive seven-season stretch in Japan (1992-98), mostly with the Chunichi Dragons. He amassed 116 home runs and 397 RBIs while posting a .313/.371/.510 slash line.
The Giants also are expected to name their pitching coach and assistant hitting coach shortly.
Chris Haft has covered the Giants since 2005, and for MLB.com since 2007. Follow him on Twitter at @sfgiantsbeat and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.